fixes and optimizations

- shared the CutPieces scene between the BeepCube and ChainLink scenes - CutPieces are now pre-instanced and live inside of their parent cube's scene tree (as opposed to reparented into the the track) - Cube slice particles are no longer dynamically instance (pre-instanced when cube is made and live in cube's scene tree, similar to the way CutPieces are managed) - rewrote a lot of the ScenePool logic. it was becoming way to specific to cube types. could potentially pool Bombs and Walls too, but performance seems ok so far ... - cleaned up old materials that are no longer used - fixed issue with the UIRayCast becoming offset independent of saber custom offsets/rotations - reduced time consumed by useless rumble API calls - improved performance of the saber tail history management (also made that code more readable by reducing triple-nested list data structure)